These techniques usually base their performance on two detection paradigms as the main attacks in spite of whether they are network or hot based architecture. Some of these models are the misuse detection models and anomaly detection models. The misuse detection model, the IDS compares the new sequences of the parameters in the input. The application matches the commands of the HTTP protocol where a database of signatures which signify the attacks that have been identified and classified before is known (Aquino et al, 2008).
This model revises and improves the disruptive commands when it experiences attacks.
The misuse detection model is not the best model to be used and it’s used as an alternative for efficiency in the medium. It can be lead to the new variations of the attacks experienced before to elude the network security. The anomaly detection model detects interruption by searching abnormal network traffic. It detects deviation by finding patterns on data from internet (Aquino et al, 2008). Example The testing of multilayer feed forward network can be done using two layers which are hidden and have15 neurons each and a 5 output neurons for a 5 possible attacks.
The network is then equipped with a flexible transmission algorithm with the neurons being sigmoid. After being trained with a dataset of 70 % it reaches a predictable error target of 0. 015 upon completion of the training sequence. When choosing the number of neurons per hidden layer, the calculation is done by subtracting the number of neurons in the output layer from the number of inputs in the system (Aquino et al, 2008). Advantages and Disadvantages Voip protocol is a security system which is designed in such a way that it optimizes the communication of aural by the use of internet (Millions, 2008).
Comparing Voip (Voice over Internet Protocol) to other security protocols, there are a number of advantages which makes Voip remain the choice of many in the present world. Therefore, Voice over Internet Protocol is efficient when it comes to their cost. Voip uses public switched telephone network. The IPSec secures the low level system packets in order for the system of computers to be protected over insecure channels which are inclusive of internet and hire lines. Voip can easily add more lines whereas the other protocols cannot. It is hard to break into the safety of the system especially when there is encryption.
Once there is power failure phones can still be used (Millions, 2008). Disadvantages There is occurrence of inconveniences in the structure once there is a large torrent of information being transferred in Voip. There is also a possibility of jitter data transfer conundrum occurrence in the system if the right precautions are not taken. Due to difficulty in the relocation of information, this can result to low overhaul superiority. Therefore, this can result into failure of the voice for the final consumers (Millions, 2008). Cryptanalysis Report Organizations are faced with the problem of receiving encrypted messages from their clients.
In order to support the clients, organizations need to understand how to decrypt the encrypted messages. In most cases, the management of the organization and the clients usually use a single-key also known as the private-key in the encryption and the decryption of the messages. This kind of encryption is known as symmetrical encryption and is widely used by many people. The original message is usually referred to as a plaintext while the encrypted message is referred to as a ciphertext (Brown, 2007, p. 4). In symmetric algorithm, the same key is used for both the encryption and the decryption process (Vajda, 2003, p.3).
The algorithm that the sender uses for changing the plaintext to a ciphertext is known as cipher. Since Charles Smith, a full-time associate in McKay IT service went on a business trip without carrying the logbook of the security protocols, there is need of using the process of cryptanalysis. This is method of code breaking the ciphertext without the use of the private key (Brown, 2007, p. 4). The process by which an original message is encrypted is shown by the formula E (M) = C. in which E is the function of encryption, M is the message and C is the Ciphertext.
For decrypting the ciphertext, the receiver needs to use the formula D (C) = M so as to get the original message. In which D is the function of decryption, C is the Ciphertext and M is the original message (Vajda, 2003, p. 1). The algorithms of encryption and decryption use the private key known to the sender and the receiver only. Therefore, the proper formula to use in both the encryption and decryption process is C = EK (M) and M = DK (C) in which K is the private Key (Vajda, 2003, p. 1). Cryptanalytic attacks occur when a person attempts a cryptanalysis of a ciphertext (Vajda, 2003, p. 3).
There are different types of cryptanalytic attacks from the sender. But for the purpose of this study, the ciphertext only attack will be used. This is because Charles and I as the consultant only know the ciphertext (Brown, 2007, p. 9). A person can use brute force search in the process of cryptanalysis by trying all possible keys (Brown, 2007, p. 11). Plaintext letter are usually substituted by number, symbols or even other letter to form the ciphertext. In this case, ciphertext that have been sent by the client has been replaced by other letters as shown
For an effective cryptanalysis, one needs to know the type of cipher that was used. One should also measure the complexity of the attack to ensure effective cryptanalysis such as complexity of the data. Complexity of the data is the data amount that needs to be decrypted. The complexity of the process also needs to be measured such as the time needed for performing the attack. Lastly, one needs to have enough storage memory for the performing the attack (Vajda, 2003, p. 6). In ciphertext only attacks, given that C1 = Ek (P1) and Ci = Ek (Pi).
In deducing P1 and Pi, Ci + 1 = Ek (Pi + 1). In cases, where the ciphertext only is available, it is hard to recover the plaintext. Therefore one can use the cryptanalysis of the Caesar cipher by trying the possible 25 shifts of keys in order to substitute the letters in the ciphertext to get the plaintext (Brown, 2007). One way of avoiding the cryptanalysis is by ensuring that the private key is only known to the sender and the receiver of the message. People should also ensure that while sending the encrypted, they give the sender the hint of the key used. Conclusion
Appropriate models of computer security protocols have been proposed all through the discussion. Attacks in the system security protocols can be detected by the use of different models. These models include the misuse detection models and anomaly detection models. The attacks that influence the protocols lead to delays in the security system. Services can be denied through a brute force attack on the server processing speed or the band width. If the security qualification of the server has part of it as authentication value, then the computation is necessary in response to every qualification request which is valid.
Alarcon-Aquino, V. , Mejia Sanchez, J. A. , Rosas-Romero, R. , Ramirez-Cruz, J. F. (2005). Detecting and Classifying Attacks in Computer Networks Using Feed-forward and Elman Neural Networks. Proceedings of the 1st European Conference on Computer Network Defense, EC2ND 2005. Wales, UK: Springer Verlag. Aquino, V. A. , Clavel C. A. , Asomoza J. R, Starostenko, O. , & Romero, R. R. (2008). Intrusion detection and Classification of attacks in High-Level Network protocols Using Recurrent Neural Networks. Retrieved December 18, 2008, from